Defining & Refining Your Lindsay Haplotype
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Defining & Refining Your Lindsay DNA HaplotypeYour decision to participate in the International Lindsay Surname DNA Project should be based first upon your willingness to define your specific Lindsay lineage DNA haplotype and then, where possible, the subsequent refining of your haplotype to ensure the most accurate comparison to other Lindsay lineage haplotypes. Hopefully this will lead to the determination of your Most Recent Common Ancestor (MRCA) via traditional genealogical research. Thus, much importance is being placed, in today's world of genetic genealogy, on the determination of the family surname, male-specific haplotype. But first, what is a male-specific surname haplotype? What is a Male-Specific Surname Haplotype?The ability to identify male-specific DNA renders Y-chromosomal
Short Tandem Repeat (STR) systems markers, discovered and published by the
genetic community, an invaluable tool in helping to ascertain the possibility of
there being a Most Recent Common Ancestor (MRCA) between two males bearing the
same surname. You can see the list of Y-chromosome markers utilized by the Lindsay Surname DNA Project on the web page found at http://www.clanlindsay.com/markers_used_by_lindsay_dna_project.htm . Potential DNA test candidates should know that the various commercial laboratories use different sets of Y-chromosome DNA markers, some overlapping while many others are totally different. This revelation should lead one to understand that to be effective, all members of a surname DNA project should use the same set of markers in defining their haplotype in order to be able to compare all of your marker values, which unfortunately translates into all participants using the same commercial laboratory. After becoming economically feasible with commercial deployment, the field of genealogy has picked up on this genetic tool and is now applying its use to help validate the multiple paths of the males of a particular surname. Obviously, the more Y-chromosome markers that are employed to define a male's haplotype the better chance you have in clearly ascertaining the affiliation of all the collateral lineages that descend from a Most Recent Common Ancestor (MRCA). Obviously, at some point, economics becomes a limiting factor in the number of markers measured. We can conclude that your male-specific surname DNA haplotype is defined as the set of allele (number of repeats of an identified arrangement of bases within a specific segment of your Y-chromosome) values that are measured by any prescribed set of Y-chromosome STR markers, whether it be sets of 12, 26, 37, 43 or 67 markers. Defining Your Lindsay HaplotypeA Lindsay male can define the haplotype of his particular Lindsay lineage by agreeing to participate in the International Lindsay Surname DNA Project whereby he will obtain the allele values for the current 43 Y-chromosome STR markers that are employed by the Lindsay DNA Project. This set of 43 marker values constitutes this Lindsay male's haplotype. Refining your Lindsay Haplotype via the Triangulation MethodThe refinement process is designed to ascertain with a higher degree of certainty, whether the DNA haplotype, that a male has established, for his particular Lindsay lineage, most likely represents that of his Lindsay progenitors (father, grandfather, great-grandfather, etc.). The haplotype refinement process must start with the testing of at least two known male cousins from a well documented Lindsay lineage. Should it be determined that these two "cousins" have any miss-matches in the repeat values of their respective 43 Y-chromosome markers, a third "cousin" from this same known Lindsay lineage would be needed to determine which set of marker values more accurately represents the "un-mutated" Y-chromosome haplotype of the MRCA for the group of specific Lindsay males being tested. Keep in mind, at this point, that if two known cousins, from a well documented Lindsay lineage, were to be tested, it is always possible to see one or two legitimate miss-matches in their markers due to predictable mutations that could occur at any biological event (birth) in our Lindsay lineages. In an attempt to demonstrate how members of any Lindsay (how ever spelled) lineage can first determine, then refine their specific Lindsay haplotype using the "triangulation method", I have employed several examples. For further clarification, I have first employed, in Slide 1, the actual situation that represents the efforts of the participants of "Lineage 1" of the Lindsay DNA Group 3 (see http://www.clanlindsay.com/dna_group_3.htm for more details regarding this Lindsay Group). It would be to your advantage, in best understanding this example, to first print the Slides in the graphics directly below and have them in your view when reading the dialog that pertains to that slide. You can easily print the slides by placing your cursor over the graphic and right click your mouse. Then select PRINT from the pull down menu. This way you only print the graphic. Notes for Slide 1 (below) Using my particular DNA Group 3 case, two 1st cousins “I”(L0011) and “J” (L0010) were the first in our family to be DNA tested. It was determined these two cousins had two, one-step mutating markers between the two of them, out of 43 markers. Our next decision was to test another 1st cousin “H”(L0051). 1st cousin “H” was found to be a perfect match with “I”. The logical conclusion now was that “I” and “H” represented the DNA haplotype of their Most Recent Common Ancestor (MRCA) grandfather “B”. Our next decision was to test our 2nd cousin “G” (L0052) where it was determined that cousins “H”, “I” and “G” were a perfect match out of 43 markers. We could now reasonable conclude that the DNA haplotype of the MRCA great-grandfather “A” was the common haplotype displayed by cousins “H”, “I” and “G”. The only question we are left with is where the two mutations occurred for cousin “J”. One or both mutations could have occurred at the birth of his father “F” or one or both could have occurred at the birth of “J” himself. “J” has a brother, “K”, that could be tested to likely prove this point.
Notes for Slide 2 On a more general scale and with a more expansive
genealogy, the following rules of triangulation apply. If siblings “H” and “I” have a perfect 43 marker match, one can conclude they have the same haplotype as that of their MRCA father “D”. If cousins “H” and “J” have a perfect 43 marker match, one can conclude they have the same haplotype as that of their MRCA grandfather “B” If cousins “H” and “L” have a perfect 43 match, one
can conclude they have the same haplotype as that of their MRCA
great-grandfather “A”. It is very likely, in many cases, where these perfect matches between cousins will not occur. The need will then arise to bring additional cousins into the testing cycle in order to ascertain the likely modal haplotype of the MRCA, unless of course you exhaust your potential supply of living male cousins before achieving your goal.
It is important that each person, who considers refining their haplotype with Triangulation Method DNA Testing, first create a genealogical proven graphic for their specific Lindsay lineage before considering the use of this tool. This will clearly show you where the possible test candidates (cousins) are and what you can hope to achieve, regarding your Lindsay lineage, with the additional testing. By using this triangulation method for refining the haplotype of your specific Lindsay lineage, you could potentially, more accurately position the merger of your Lindsay lineage Most Recent Common Ancestor (MRCA) with another Lindsay lineage that has also been DNA tested. Hopefully, in the process, we can also gain some additional insight into the potential mutation rate of the Y-chromosome DNA for our Lindsay lineages. Date This Page Was Initially Posted: November 2001 Date Last Modified &Updated: February 14, 2007Since April 23, 2003, you are visitor #
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